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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Παρακολούθηση της οικολογικής ποιότητας παράκτιων οικοσυστημάτων Ελλάδας και Κύπρου στα πλαίσια εφαρμογής της οδηγίας 2000/60/ΕΕ για τα ύδατα: λιμνοθάλασσες Κοτύχι-Πρόκοπος, αλυκές Λάρνακας-Ακρωτηρίου

Τζιωρτζιής, Ιάκωβος 23 October 2008 (has links)
Τα παράκτια μεταβατικά οικοσυστήματα όπως οι λιμνοθάλασσες και οι αλυκές, αποτελούν δυναμικά οικοσυστήματα και παρουσιάζουν έντονες χωρικές και χρονικές διακυμάνσεις, αφού ως οικότονοι μεταξύ ξηράς και θάλασσας, δέχονται την ταυτόχρονη επίδραση χερσαίου και θαλάσσιου περιβάλλοντος. Παράλληλα είναι οικοσυστήματα υψηλής παραγωγικότητας, αφού φιλοξενούν είδη με υψηλή πρωτογενή παραγωγικότητα. Τα υδρόβια μακρόφυτα αποτελούν δομικά και λειτουργικά στοιχεία των οικοσυστημάτων αυτών και σύμφωνα με την Οδηγία Πλαίσιο 2000/60/ΕΕ, αποτελούν ποιοτικά στοιχεία και χρησιμοποιούνται ως βιοδείκτες για την εκτίμηση της οικολογικής ποιότητας των υδάτινων οικοσυστημάτων. Στα πλαίσια της παρούσας μεταπτυχιακής διατριβής, διερευνήθηκαν οι σχέσεις μεταξύ αβιοτικών και βιοτικών παραμέτρων της υδάτινης στήλης, στις λιμνοθάλασσες Κοτύχι και Πρόκοπο της ΒΔ Πελοποννήσου και στις αλυκές Λάρνακας και στον υγρότοπο Ακρωτηρίου (Αλυκές Ακρωτηρίου, λιβάδι Φασουρίου) της Κύπρου. Πραγματοποιήθηκαν μηνιαίες δειγματοληψίες κατά την βλαστητική περίοδο των ετών 2006, 2007 και 2008, στην διάρκεια των οποίων καταγράφηκαν οι φυσικοχημικές παράμετροι των υδάτων, όπως βάθος (m), διαφάνεια (m), θερμοκρασία (οC), αλατότητα (‰), αγωγιμότητα (mS/cm), διαλυμένο οξυγόνο (mg/l), pH, ολικά αιωρούμενα στερεά (mg/l), φωτοσυνθετικά ενεργή ακτινοβολία- PAR ενώ υπολογίστηκαν οι συγκεντρώσεις της Chl-α (mg/m3) η αλκαλικότητα (mg/l), η συγκέντρωση των θρεπτικών αλάτων φωσφόρου-SRP (mg/l) και αζώτου - NO2-N, NO3-N και ΝΗ4-Ν (mg/l), καθώς και η σταθερά απορρόφησης Κ (m-1) της υδάτινης στήλης. Παράλληλα συλλέχθηκαν ποσοτικά και ποιοτικά δεδομένα που αφορούν τη δομή των μακροφυτικών κοινωνιών, καθώς και την χωρική και χρονική διακύμανση της κατανομής και της ανάπτυξης των μακροφυτικών ειδών που απαντώνται στις λιμνοθάλασσες και στις αλυκές. Τέλος διερευνήθηκαν οι σχέσεις μεταξύ αβιοτικών παραμέτρων και ειδών μακροφύτων και εξετάστηκαν οι πιθανοί παράγοντες που επηρεάζουν την ανάπτυξη και την κατανομή των μακροφύτων. Για την διερεύνηση της δομής των μακροφυτικών κοινωνιών, την ταξινόμηση της υδρόβιας βλάστησης σε ευδιάκριτες ομάδες, καθώς και την ομαδοποίηση των σταθμών δειγματοληψίας ανάλογα με την σύνθεση της βλάστησης τους, εφαρμόστηκαν οι μέθοδοι ταξινόμησης TWINSPAN και MDS. Χρησιμοποιήθηκαν επίσης οι συντελεστές συσχέτισης Pearson (r) και Kendall (tau-b), προκειμένου να εξεταστεί η ύπαρξη πιθανών συσχετίσεων μεταξύ των φυσικοχημικών παραμέτρων, αλλά και μεταξύ βιοτικών και αβιοτικών παραμέτρων, ενώ πραγματοποιήθηκε ανάλυση διασποράς (one-way ANOVA) προκειμένου να διαπιστωθούν στατιστικά σημαντικές διαφορές μεταξύ των περιοχών μελέτης, αλλά και μεταξύ των διαφορετικών ομάδων βλάστησης. Τέλος, για την διερεύνηση των αβιοτικών παραμέτρων που επηρεάζουν την ανάπτυξη και την κατανομή των μακροφύτων, εφαρμόστηκε η μέθοδος ανάλυσης κανονικών αντιστοιχιών CCA (Canonical Correspondence Analysis). Στις τέσσερις περιοχές μελέτης καταγράφηκαν συνολικά 29 taxa μακροφύτων, τα οποία ταξινομήθηκαν σε έξι ομάδες βλάστησης. Πέντε taxa από αυτά, αναφέρονται για πρώτη φορά στην Κύπρο. Τα είδη με την μεγαλύτερη αφθονία στις περιοχές μελέτης ήταν τα Ruppia cirrhosa, Potamogeton pectinatus, Najas marina ssp. armata, Althenia filiformis, Lamprothamnium papulosum και Ulva lactuca. Η βιομάζα των κυρίαρχων ειδών παρουσίασε εποχικές διακυμάνσεις με τις μέγιστες τιμές να καταγράφονται την άνοιξη και το καλοκαίρι. Στις λιμνοθάλασσες Κοτύχι και Πρόκοπο παρατηρήθηκε οικολογική διαδοχή ειδών στη διάρκεια της βλαστητικής περιόδου, η οποία μπορεί να αποδοθεί σε σημαντικές αλλαγές του αβιοτικού περιβάλλοντος (π.χ. αλατότητας), όπως η αντικατάσταση του είδους Potamogeton pectinatus από το αγγειόσπερμο Ruppia cirrhosa, ενώ η εμφάνιση ευτροφικών φαινομένων με σημαντική αύξηση της βιομάζας ευκαιριακών ειδών (π.χ. χλωρόφυτα), οδήγησε στην μείωση της βιομάζας των αγγειοσπέρμων. Στις αλυκές Λάρνακας και Ακρωτηρίου η βιομάζα κυμάνθηκε σε πολύ χαμηλά επίπεδα πιθανώς λόγω των πολύ ψηλών τιμών αλατότητας. Τις υψηλότερες τιμές βιομάζας παρουσίασε το αγγειόσπερμο Althenia filiformis τον Απρίλιο. Την βλαστητική περίοδο 2008 οι μεγαλύτερες τιμές αλατότητας που καταγράφηκαν στις αλυκές Λάρνακας και Ακρωτηρίου, δεν ευνόησαν την ανάπτυξη μακροφύτων. Αντίθετα στο λιβάδι Φασουρίου όπου η αλατότητα ήταν σημαντικά χαμηλότερη, η βιομάζα του κυρίαρχου Najas marina ssp. armata κυμάνθηκε σε υψηλές τιμές με τις μεγαλύτερες να καταγράφονται τον Ιούνιο. Από την διερεύνηση των μορφομετρικών χαρακτηριστικών του αγγειόσπερμου Ruppia cirrhosa, προέκυψε ότι η πυκνότητα των πληθυσμών του είδους κυμάνθηκε στα ίδια επίπεδα με άλλες λιμνοθάλασσες της Μεσογείου (449–5120 βλαστοί/m2), ενώ παρουσίασε θετική συσχέτιση με την θερμοκρασία και αρνητική συσχέτιση με την συγκέντρωση ολικού φωσφόρου. Το μήκος των φύλλων συσχετίστηκε θετικά με την συγκέντρωση των όξινων ανθρακικών ιόντων, τα οποία σε χαμηλές συγκεντρώσεις μπορεί να αποτελέσουν περιοριστικό παράγοντα για την ανάπτυξη των μακροφύτων. Η μεγαλύτερη ποικιλότητα μακροφύτων (δείκτης Shannon-Weaner) καταγράφηκε στην λιμνοθάλασσα Πρόκοπο, ενώ οι αλυκές Λάρνακας παρουσίασαν την χαμηλότερη ποικιλότητα, πιθανά λόγω του ότι οι υψηλές τιμές αλατότητας δεν ευνοούν την ανάπτυξη πολλών ειδών μακροφύτων. Η εφαρμογή του δείκτη οικολογικής αξιολόγησης ΕΕΙ (Ecological Evaluation Index) για την εκτίμηση της οικολογικής ποιότητας των υδάτων με την χρήση των μακροφύτων ως βιοδεικτών, είχε ως αποτέλεσμα την ταξινόμηση της ποιότητας των υδάτων της λιμνοθάλασσας Κοτυχίου ως Μέτρια, της λιμνοθάλασσας Πρόκοπος και των αλυκών Λάρνακας ως Καλή, ενώ του υγρότοπου Ακρωτηρίου μπορούν να χαρακτηριστούν ως Υψηλής οικολογικής ποιότητας. Oι σημαντικότερες περιβαλλοντικές παράμετροι που καθορίζουν την σύνθεση των ομάδων βλάστησης, αλλά και την εξάπλωση των ειδών των μακροφύτων στις περιοχές έρευνας, είναι το υδατικό ισοζύγιο, η αλατότητα και οι συγκεντρώσεις των θρεπτικών αλάτων. Στα πλαίσια προστασίας και διατήρησης των παράκτιων αυτών υγροτόπων, προτείνεται ο σχεδιασμός ενός μόνιμου δικτύου παρακολούθησης βιοτικών και αβιοτικών παραμέτρων και η διεξαγωγή συστηματικής έρευνας με την πραγματοποίηση οικολογικών μελετών χρησιμοποιώντας βιοτικά στοιχεία για την εκτίμηση της οικολογικής τους ποιότητας. Επίσης, η λήψη διαχειριστικών μέτρων για τον περιορισμό της εισροής θρεπτικών στους υγρότοπους, κρίνεται επιτακτική αφού η εμφάνιση ευτροφικών φαινομένων αποτελεί διαρκεί απειλή για τα υδάτινα οικοσυστήματα. Η απαγόρευση καταπάτησης των οικοτόπων, της απόρριψης σκουπιδιών, της βόσκησης και της θήρευσης, μπορεί να υλοποιηθεί με την λήψη και εφαρμογή αυστηρών μέτρων, καθώς και με την φύλαξη των περιοχών αυτών. Η περίφραξη και η σηματοδότηση επιλεγμένων σημείων, ο καθαρισμός απορριμμάτων, η απομάκρυνση ξενικών ειδών και ο καθαρισμός των καναλιών που συλλέγουν και διοχετεύουν νερό από την λεκάνη απορροής στους υγρότοπους, μπορούν να βοηθήσουν στην διατήρηση των υγροτόπων και την βελτίωση της οικολογικής τους κατάστασης. Επίσης, η πραγματοποίηση ειδικών περιβαλλοντικών μελετών πρέπει πάντα να προηγείται της υλοποίησης κάθε μορφής έργων. Τέλος η ενημέρωση και ευαισθητοποίηση του κοινού με την απρόσκοπτη λειτουργία κέντρων περιβαλλοντικής ενημέρωσης και φορέων διαχείρισης των περιοχών αυτών, κρίνεται απαραίτητη προκειμένου οι υγρότοποι να προστατευτούν και να αποφευχθεί η σταδιακή υποβάθμιση τους. / Lagoons and other coastal wetlands are shallow aquatic environments located in the transitional zone between terrestrial and marine ecosystems, which can span from freshwater to hypersaline conditions depending on their water balance. They exhibit an extreme spatial and temporal variability of environmental parameters and are recognized as highly productive ecosystems. Aquatic macrophytes are key structural and functional components of aquatic ecosystems. As photosynthetic sessile organisms being at the base of food web, are vulnerable and adaptive to human and environmental stress. They respond to aquatic environment representing reliable indicators of its changes and are mentioned in the WFD as biological quality elements for the ecological classification of transitional and coastal waters. In the present work, the relationships between biotic and abiotic parameters of the water column were investigated in coastal lagoons of Kotychi and Prokopos (NW Peloponnisos, Greece), Larnaca salt lakes and Akrotiri wetland (Cyprus). Monthly samplings were conducted during the vegetative periods of the years 2006, 2007 and 2008 and water parameters such as depth (m), transparency (m), temperature (οC), salinity (‰), conductivity (mS/cm), dissolved oxygen (mg/l), pH, photosynthetic active radiation – PAR and attenuation coefficient K (m-1) were recorded in situ, while Chl-α (mg/m3), total suspended matter (mg/l), alkalinity and nutrients of nitrogen and phosphorus (mg/l) were determined in the laboratory. Quantitative and qualitative data concerning aquatic macrophyte flora were recorded during the same period, such as species composition, community structure, spatial and temporal variations of species abundance and the succession of submerged macrophytes in relation to the main environmental factors. The aquatic macrophytic community was distinguished in different vegetation groups using TWINSPAN and MDS techniques. Correlations between environmental parameters were tested using Pearson and Kendall correlation tests, while One –way ANOVA was used to determine statistical significant differences of environmental variables between different study areas and distinguished plant groups. Finally CCA was performed in order to examine relationships between the species abundance and environmental variables. In total, 29 taxa were recorded in all four study areas and were classified in six vegetation groups. Five species were recorded for the first time in the island of Cyprus. The most abundant species were Ruppia cirrhosa, Potamogeton pectinatus, Najas marina ssp. armata, Althenia filiformis, Lamprothamnium papulosum και Ulva lactuca. The biomass of dominant species showed seasonal variations and maximum biomass values were recorded in late spring and summer. In Kotychi and Prokopos lagoons, the replacement of Potamogeton pectinatus by Ruppia cirrhosa was recorded, probably due to significant increase of salinity. In other parts of the lagoons, the replacement of macrophyte beds due to increased macroalgal proliferation was also recorded. In Larnaca and Akrotiri salt lakes, biomass values were significantly lower as a result of high salinity values. The most abundant species was Althenia filiformis (biomass peak in April). During the vegetative period of 2008, extreme salinity values were recorded as a result of reduced rainfall. High salinity values resulted in scarse occurrence of macrophytes in the salt lakes during this period. In Fasouri marsh, which is characterized by minimum salinity values, the dominant species Najas marina ssp. armata showed high biomass values (peak in June). Regarding the results of Ruppia cirrhosa population’s density in Kotychi lagoon (449-5120 shoots/m2), they were comparable with data from other Mediterranean lagoons. Meadows density was positively correlated with temperature and negatively correlated with total phosphorus. Leaf length showed positive correlation with bicarbonate ions, which can be a restrictive factor for the growth of macrophytes. The highest macrophyte diversity (Shannon-Weaner index) was found in Prokopos lagoon, whereas Larnaca salt lakes had the lowest values, probably due to high salinity. The implementation of EEI (Ecological Evaluation Index) for the assessment of the ecological quality of coastal and transitional waters, showed that Kotychi lagoon was classified into Moderate ecological class. Prokopos lagoon and Larnaca salt lakes were classified into Good ecological class and finally Akrotiri wetland was classified into High ecological class. Hydrological regime, salinity and nutrient concentrations seem to be the key factors controlling macrophyte composition, community structure and species abundance. For the conservation and management of these coastal and transitional wetlands, we propose the development of a monitoring network for biotic and abiotic parameters. Ecological studies for the evaluation of ecological quality of the wetlands according to the WFD 200/60/EU and implementation of management practices for the reduction of nutrient inflows in the wetlands are needed, in order to reduce eutrophication phenomena, which are a severe threat for the ecological balance of the wetlands. The encroachment of wetlands, hunting and waste discharges, should be prohibited by law. Finally, the increase of public environmental awareness will have significant results in the conservation of coastal wetlands.
132

Phytoplankton dynamic in permanent and temporary waters of Empordà Salt marshes (NE Spain)

López i Flores, Rocío 05 July 2005 (has links)
Se ha estudiado la dinámica del fitoplancton en las lagunas costeras de Aiguamolls de l'Empordà. El fitoplancton esta sujeto principalmente al control "bottom-up", la variabilidad hidrológica y la disponibilidad de nutrientes tienen una mayor influencia en la composición y distribución de tamaños del fitoplancton, que el zooplancton. La concentración de materia orgánica disuelta es el factor ambiental más correlacionado con el crecimiento de la biomasa fitoplanctónica. Dada la proximidad entre las lagunas costeras y el mar, donde la ocurrencia de Proliferaciones de Algas Nocivas es cada vez más frecuente, se realizan un inventario general de las especies más abundantes del fitoplancton y se llevan a cabo análisis extensivos de la toxicidad. La mayoría de especies de dinoflagelados encontradas son potencialmente nocivas. Hay pocas especies en común entre el mar y las lagunas, sin embargo, existen especies productoras de PANs características de los ambientes lagunares. / The phytoplankton dynamics in the coastal lagoons of Empordà salt marshes was studied. The phytoplankton was mainly subject to the "bottom-up" control, the hydrologic variability and the nutrients availability have a greater influence in the composition and size distribution of the phytoplankton, than zooplankton. The concentration of dissolved organic matter was the environmental factor more correlated with the phytoplanktonic biomass growth. Due to the proximity between the coastal lagoons and the sea environment, where the occurrence of Harmful Algae Blooms is frequent, a general inventory of the most abundant species of the phytoplankton was made and an extensive monitoring of the toxicity was carried out. Most of dinoflagellates species found were potentially harmful. There were few species in common between the sea and the lagoons, nevertheless, some HABs species, characteristic of coastal lagoons, were found.
133

Cianobactérias como parâmetro de qualidade ambiental: um estudo no complexo lagunas de Jacarepaguá. / Cyanobacteria as environmental quality parameters: a study in Jacarepaguá lagoon complex.

Gláucia Freitas Sampaio 07 March 2008 (has links)
O Complexo Lagunar de Jacarepaguá, localizado no município do Rio de Janeiro, região sudeste do Brasil, é formado pelas lagunas de Jacarepaguá, Camorim, Tijuca e Marapendi. Estas lagunas estão interligadas ao mar pelo canal da Joatinga e têm como afluentes rios e canais que vertem dos maciços da Tijuca e da Pedra Branca. Recebem esgotos sanitários e efluentes industriais, além de contribuições difusas de águas de drenagem e circulação das massas de águas de várias origens, com elevada carga de poluição. A eutrofização cultural aliada aos processos de evolução de ecossistemas costeiros produziu um estado de degradação destas águas com constantes florações de cianobactérias potencialmente tóxicas. O presente estudo tem como objetivo avaliar a ocorrência das cianobactérias (Classe Cyanophyceae) no Complexo Lagunar de Jacarepaguá e corroborar a hipótese de serem boas indicadoras de qualidade ambiental de águas salobras. Foi realizado um monitoramento ambiental nas lagunas de Jacarepaguá, Camorim, Tijuca e Marapendi, nos anos de 2004 a 2006, sendo analisados parâmetros físicos, químicos e biológicos. Os resultados obtidos demonstraram a dominância e a persistência das cianobactérias em elevadas concentrações de nutrientes, caracterizando a hipereutrofização dessas lagunas. As estratégias ecológicas das cianobactérias garantiram sua dominância em quase todo o período amostral e demonstraram ser um refinado sensor das variáveis ambientais. A salinidade não foi um fator de limitação ao desenvolvimento desses microorganismos. Desta forma, este estudo, oferece subsídios para gestão de recursos hídricos, corroborando com a legislação CONAMA 357/05-MMA, na sugestão de indicação deste parâmetro de qualidade ambiental também para ambientes salobros na classe 1. / The Jacarepaguá Lagoon Complex, located in the state of the Rio of Janeiro, in Southeast of Brazil, is formed by the lagoons of Jacarepaguá, Camorim, Tijuca and Marapendi. These lagoons are interconnected to the sea by the Joatinga canal and receive contribution from tributary rivers and channels that come from Tijuca and Pedra Branca massifs. They receive industrial and domestic effluents, including diffuse contributions of the drainage basin, as well as water circulation from several origins, with a high pollution load. The cultural eutrophication associated with coastal ecosystems evolution processes, have produced a state of degradation of these waters with frequent waterblooms of potentially toxic cyanobacteria. The objective of the present study is to evaluate the presence of Cyanobacteria (Class Cyanophyceae) in the Jacarepaguá Lagoon Complex and also to corroborate the hypothesis of using them as a good bioindicators of environmental quality in brackish waters. An environmental monitoring program has been carried out in the lagoons of Jacarepaguá, Camorim, Tijuca and Marapendi from 2004 to 2006, including physical, chemical and biological parameters analysis. The results showed the dominance and persistence of Cyanobacteria at high concentrations of nutrients, characterizing the hypereutrofication of these lagoons. The ecological strategies of Cyanobacteria were responsible for their dominance in almost the whole period of study and demonstrated that they can be used as a good sensor of environmental variables. The salinity did not demonstrate to be a limiting factor to the development of these microorganisms. In this way, this study provides subsidies for water resources management, corroborating with Brazilian legislation (CONAMA 357/05- MMA) suggesting the inclusion of Cyanobacteria as a parameter of environmental quality in brackish environments classified as Class 1.
134

Cianobactérias como parâmetro de qualidade ambiental: um estudo no complexo lagunas de Jacarepaguá. / Cyanobacteria as environmental quality parameters: a study in Jacarepaguá lagoon complex.

Gláucia Freitas Sampaio 07 March 2008 (has links)
O Complexo Lagunar de Jacarepaguá, localizado no município do Rio de Janeiro, região sudeste do Brasil, é formado pelas lagunas de Jacarepaguá, Camorim, Tijuca e Marapendi. Estas lagunas estão interligadas ao mar pelo canal da Joatinga e têm como afluentes rios e canais que vertem dos maciços da Tijuca e da Pedra Branca. Recebem esgotos sanitários e efluentes industriais, além de contribuições difusas de águas de drenagem e circulação das massas de águas de várias origens, com elevada carga de poluição. A eutrofização cultural aliada aos processos de evolução de ecossistemas costeiros produziu um estado de degradação destas águas com constantes florações de cianobactérias potencialmente tóxicas. O presente estudo tem como objetivo avaliar a ocorrência das cianobactérias (Classe Cyanophyceae) no Complexo Lagunar de Jacarepaguá e corroborar a hipótese de serem boas indicadoras de qualidade ambiental de águas salobras. Foi realizado um monitoramento ambiental nas lagunas de Jacarepaguá, Camorim, Tijuca e Marapendi, nos anos de 2004 a 2006, sendo analisados parâmetros físicos, químicos e biológicos. Os resultados obtidos demonstraram a dominância e a persistência das cianobactérias em elevadas concentrações de nutrientes, caracterizando a hipereutrofização dessas lagunas. As estratégias ecológicas das cianobactérias garantiram sua dominância em quase todo o período amostral e demonstraram ser um refinado sensor das variáveis ambientais. A salinidade não foi um fator de limitação ao desenvolvimento desses microorganismos. Desta forma, este estudo, oferece subsídios para gestão de recursos hídricos, corroborando com a legislação CONAMA 357/05-MMA, na sugestão de indicação deste parâmetro de qualidade ambiental também para ambientes salobros na classe 1. / The Jacarepaguá Lagoon Complex, located in the state of the Rio of Janeiro, in Southeast of Brazil, is formed by the lagoons of Jacarepaguá, Camorim, Tijuca and Marapendi. These lagoons are interconnected to the sea by the Joatinga canal and receive contribution from tributary rivers and channels that come from Tijuca and Pedra Branca massifs. They receive industrial and domestic effluents, including diffuse contributions of the drainage basin, as well as water circulation from several origins, with a high pollution load. The cultural eutrophication associated with coastal ecosystems evolution processes, have produced a state of degradation of these waters with frequent waterblooms of potentially toxic cyanobacteria. The objective of the present study is to evaluate the presence of Cyanobacteria (Class Cyanophyceae) in the Jacarepaguá Lagoon Complex and also to corroborate the hypothesis of using them as a good bioindicators of environmental quality in brackish waters. An environmental monitoring program has been carried out in the lagoons of Jacarepaguá, Camorim, Tijuca and Marapendi from 2004 to 2006, including physical, chemical and biological parameters analysis. The results showed the dominance and persistence of Cyanobacteria at high concentrations of nutrients, characterizing the hypereutrofication of these lagoons. The ecological strategies of Cyanobacteria were responsible for their dominance in almost the whole period of study and demonstrated that they can be used as a good sensor of environmental variables. The salinity did not demonstrate to be a limiting factor to the development of these microorganisms. In this way, this study provides subsidies for water resources management, corroborating with Brazilian legislation (CONAMA 357/05- MMA) suggesting the inclusion of Cyanobacteria as a parameter of environmental quality in brackish environments classified as Class 1.
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Tributários de um reservatório neotropical: habitats de desova e desenvolvimento inicial de peixes / Tributaries of a neotropical reservoir: spawning habitats and early development of fish

Silva, Patricia Sarai da 19 August 2011 (has links)
Made available in DSpace on 2017-07-10T18:13:30Z (GMT). No. of bitstreams: 1 Patricia S da Silva.pdf: 3404031 bytes, checksum: 5e4338885b036077d4619e4525d56526 (MD5) Previous issue date: 2011-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to analyze spatial and temporal patterns of ichthyoplankton in tributaries (Aguapeí, Verde, Pardo and Anhanduí) of Porto Primavera Reservoir, Upper Paraná River, Brazil, and its relation to some environmental variables. Specifically we sought to (I) assess whether the tributaries have similar abiotic characteristics, (II) verify that abiotic factors have more influence in the spawning of the species, (III) investigate if the species have preference for tributaries, and (IV) analyze whether the tributaries of the Porto Primavera Reservoir are really suitable environments for reproduction of fish species, especially long-distance migratory drastically affected by impoundments. Samples were taken monthly during three spawning seasons (October to March from 2007 to 2010), through horizontal hauls on the water surface at dusk, with a plankton net. The principal component analysis (PCA) was used to ascertain whether the abiotic variables differed among the tributaries. The influence of environmental variables (water temperature, pH, electrical conductivity, dissolved oxygen, turbidity, water level and discharge) in the abundance of eggs and larvae was determined using the Bioenv procedure. The Kruskal-Wallis (KW) was applied to verify spatial (tributaries: rivers Aguapeí, Verde, Pardo and Anhanduí; and habitats: main channel and lagoon) and temporal distribution patterns (month: October, November, December, January, February, and March, and spawning seasons: 1 =2007/2008, 2=2008/2009, and 3=2009/2010). The characteristic taxa of each tributary were identified through Indicator Species Analysis (IndVal). A total of 49,072 eggs, 63,857 larvae were captured. The variable that best correlated with the distribution and abundance of ichthyoplankton was the water discharge. The highest densities of eggs were noted for the Verde river, however larvae did not differ significantly among the tributaries. Eggs had the highest densities in the main channel and while larvae in lagoons. High catches of ichthyoplankton were observed from November to January, but with a peak in December. Abundance of eggs were higher in the 2009/2010 spawning season, however the larvae did not differ among spawning season. The species composition varies along the tributaries and each river has a group of indicator species. In main channel of the rivers were mainly found larvae of migratory species of short distance and long-distance and in the lagoons mainly sedentary or migratory species of short distances. The tributaries assessed are spawning grounds for many fish species and can be considered suitable for the reproduction of many long-distance migratory species. Establishment and enlargement of Conservation Units in tributaries of Porto Primavera reservoir, can help preserve habitats identified as essential spawning and nursery areas, and can be key to the maintenance and conservation of the fish species in the upper Paraná River basin. / O objetivo deste trabalho foi analisar padrões espaciais e temporais do ictioplâncton em tributários (Aguapeí, Verde, Pardo e Anhanduí) do reservatório de Porto Primavera, alto rio Paraná, Brasil, e sua relação com algumas variáveis ambientais. Especificamente procurou se (I) Avaliar se os tributários apresentam características abióticas similares, (II) Verificar que fatores abióticos exercem maior influência na desova das espécies, (III) Averiguar se há preferência das espécies de peixes quanto aos tributários, e (IV) Analisar se os tributários do reservatório de Porto Primavera realmente são ambientes adequados à reprodução das espécies de peixes, em especial as migradoras de longa distância drasticamente afetadas pelos represamentos. As amostragens foram realizadas durante três estações reprodutivas sucessivas (outubro a março de 2007 a 2010), ao anoitecer com rede de plâncton. A análise de componentes principais (ACP) foi empregada para averiguar se as variáveis abióticas diferiam entre os tributários. A influência das variáveis ambientais (temperatura da água, pH, condutividade elétrica, oxigênio dissolvido, turbidez, nível e vazão) na abundância de ovos e larvas foi determinada através do procedimento Bioenv. O teste de Kruskall Wallis (K-W) foi aplicado para verificar padrões de distribuição espacial (tributários: rios Aguapeí, Verde, Pardo e Anhanduí; e habitats: rio e lagoa) e temporal (meses: outubro, novembro, dezembro, janeiro, fevereiro e março; e estações reprodutivas: 1 = 2007/2008, 2 = 2008/2009 e 3 = 2009/2010). Os táxons característicos de cada tributário foram identificados por meio da Análise de Espécies Indicadoras (IndVal). Um total de 49.072 ovos, 63.857 larvas foi capturado. A variável que melhor se correlacionou com a distribuição e abundância do ictioplâncton foi a vazão. As maiores densidades de ovos foram verificadas para o rio Verde, porém as de larvas não diferiram significativamente entre os tributários. Ovos apresentaram maiores densidades nos rios e as larvas nas lagoas. Capturas elevadas do ictioplâncton foram observadas de novembro a janeiro, porém com pico em dezembro. As capturas de ovos se sobressaíram na estação reprodutiva de 2009/2010, no entanto, as de larvas não diferiram entre as estações reprodutivas. A composição das espécies ao longo dos tributários varia e cada rio apresenta um grupo de espécies indicadoras. Nos rios foram encontrados principalmente larvas de espécies migradoras de curta e longa distância e nas lagoas principalmente de espécies sedentárias ou migradoras de curta distância. Os tributários analisados atuam como área de desova de várias espécies de peixes e podem ser considerados propícios para a reprodução de várias espécies migradoras de longa distância. A criação e ampliação de Unidades de Preservação Permanente nos tributários do reservatório de Porto Primavera podem auxiliar na preservação dos habitats identificados como áreas essenciais para a desova e berçário, e pode ser a chave para a manutenção e conservação das espécies de peixes na bacia do alto rio Paraná.
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Origem e destino da matéria orgânica do sistema lagunar Mundaú- Manguaba, AL, Brasil: sinais de cana de açucar

Nazario, Mariana Gallucci 01 February 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-02-01T18:17:45Z No. of bitstreams: 1 dissertação Mariana.pdf: 2676586 bytes, checksum: f84c5dd984b98dd78c0816e6a516bacc (MD5) / Made available in DSpace on 2017-02-01T18:17:45Z (GMT). No. of bitstreams: 1 dissertação Mariana.pdf: 2676586 bytes, checksum: f84c5dd984b98dd78c0816e6a516bacc (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências- Geoquímica, Niterói, RJ. / Este trabalho teve como objetivo avaliar as condições atuais do impacto da cana-de-açúcar nos sedimentos superficiais do Sistema Lagunar Mundaú- Manguaba, estado de Alagoas, litoral nordeste do Brasil. Nas ultimas três décadas, aproximadamente metade das bacias de drenagem no entorno do sistema estiveram cobertas por lavouras de cana. A utilização de marcadores geoquímicos orgânicos na determinação da origem da matéria orgânica tem-se mostrado uma ferramenta importante na avaliação da magnitude da poluição de sistemas lagunares por atividades agrícolas. Análises da composição elementar do carbono e nitrogênio orgânico (razão C:N) e isotópica do carbono (d13C), associadas à determinação de carboidratos e ligninas foram realizadas em 30 amostras de sedimentos totais ao longo das duas lagunas, canais e principais rios, bem como nas frações fina e grossa dos sedimentos. Além disso, foram analisadas 8 amostras de solo, procurando abranger todos os estágios de plantio da cana. A distribuição dos compostos analisados evidenciou a compartimentação do sistema em setores distintos, sugerindo que ocorram diferentes padrões de produção, introdução e degradação de matéria orgânica em cada região. De uma maneira geral, os valores de C:N e d13C indicam a presença de material autóctone nas partes centrais das lagunas e nos canais, a influência de fontes terrestres nos rios e uma mistura entre os dois tipos de material nas saídas dos rios. Nas amostras de solo foram verificadas o sinal característico de plantas C4, como a cana, com d13C próximo a -15‰ e razão C:N de 16, em média. A baixa razão C:N dos solos pode ser resultado, principalmente, da introdução de fertilizantes nitrogenados. As razões carboidrato:carbono foram mais elevadas nos solos e rios, indicando a presença de material vegetal. Da mesma forma, as maiores concentrações de ligninas (?) foram encontradas nas desembocaduras dos rios, evidenciando o aporte de material terrestre nesses locais. A distribuição das razões dos grupos fenólicos (S/V e C/V) não se mostrou muito distinta entre as estações, mas na maioria das amostras apresentou valores elevados da razão C/V, indicando a contribuição de angiospermas não lenhosas, tais como a cana, na composição de ligninas. Foi verificada a evidência de contribuição alóctone nas partes medianas das lagunas, mas os altos valores da relação entre as formas ácida e aldeídica do grupo vanilina [(Ad/Al)v] identificam o estágio avançado da degradação desse material, mascarando sinais específicos da cana. A entrada de matéria orgânica nas lagunas contribui para o aumento da produtividade primária, fato evidenciado pelas maiores concentrações de carboidratos nas regiões centrais. De uma maneira geral, as frações finas apresentaram-se enriquecidas em carbono e carboidratos, enquanto que valores elevados de ligninas e C:N, associados a valores de d13C mais leves, indicam que a fração grossa dos rios e região montante das lagunas é constituída principalmente por fragmentos vegetais. Os rios Paraíba do Meio e Mundaú apresentaram maior participação de cana em seus sedimentos, com 44% e 39%, respectivamente, enquanto que o rio Sumaúma apresenta aproximadamente 15% de cana em sua estação após a usina. O material lixiviado das bacias de drenagem provavelmente já é introduzido nos rios bastante processado, devido ao constante revolvimento e manejo dos solos. / This work aims to evaluate the actual conditions of sugar cane impact on the superficial sediments of Mundaú-Manguaba Lagoon System, State of Alagoas, Northeastern Brazil. During the last three decades, almost half of catchments areas around the system have been covered by sugar cane crops. Organic geochemistry tracers are currently used for the determination of organic matter origin as important tools for the pollution evaluation in lagoon systems affected by agricultural activities. Organic carbon and nitrogen analysis (ratio C:N), carbon isotopic analysis and carbohydrates and lignins determination were performed among 30 samples of course and fine fractions from two lagoons, channels and main rivers. Eight soil samples were also analyzed in order to represent all sugar cane cultivation stages. The compounds distribution showed the system partition to distinct sectors suggesting that different patterns of organic matter production, introduction and degradation occur in each regions. Overall, C:N e d13C values indicate presence of autochthonous material along central parts of lagoons and channels, influence of terrigenous source in rivers and a mixture of both materials at rivers outlets. The characteristic signal of C4 plants like sugar cane, were found in soil samples: d13C near to -15‰ and C:N ratio average 16. Lower C:N ratios may result, mainly, from the introduction of nitrogen fertilizers. Carbohydrate:carbon ratios were higher in soil and rivers, which indicate the presence of vegetal fragments. In the same way, higher lignin (?) concentrations were found at rivers outlets, showing the input of terrigenous sources at these locations. The distribution of phenoic groups ratios (S/V e C/V) were not significantly distinct between samples, but most of them had high values of C/V ratio, which indicates the contribution of non-woody angiosperms to lignins composition. There is an evidence of alochthonous contribution at median sectors, but high values of the acid:aldehyde ratios of vanillyl group [(Ad/Al)v] able the identification of advanced degradation stage of this material, hiding the specific signature of sugar cane. The input of organic matter in the lagoons improves the primary production, as showed by higher concentrations of carbohydrates in central sectors. In general, fine fractions had higher carbon and carbohydrate content. Meanwhile, higher values of lignins and C:N associated with lighter values of d13C indicate that the course fraction from rivers and month lagoons sector is constituted mainly by vegetal fragments. Paraíba do Meio and Mundaú rivers sediments presented higher sugar cane content, with 44% and 39% respectively, while sugar cane content was close to 15% in the station close to the plant in Sumaúma River. The leaching material from the cachtment area already reaches the rivers in a highlyprocessed form due to the constant mixture and management of the soils.
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Fluxos de amônia e óxido nitroso na interface ar-água do sistema lagunar de Maricá-Guarapina

Couto, Vanessa Barcelos 16 May 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-05-16T17:00:09Z No. of bitstreams: 1 Microsoft Word - Vanessa Dissertaçao.pdf: 1678884 bytes, checksum: ee88f8d0505bb8844a68dc56e1473779 (MD5) / Made available in DSpace on 2017-05-16T17:00:09Z (GMT). No. of bitstreams: 1 Microsoft Word - Vanessa Dissertaçao.pdf: 1678884 bytes, checksum: ee88f8d0505bb8844a68dc56e1473779 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / Este estudo analisa os fluxos de óxido nitroso (N 2 O) e amônia (NH 3 ) no Sistema Lagunar de Maricá-Guarapina (SLMG). O N 2 O é um dos gases do efeito estufa e está envolvido no consumo de ozônio (O 3 ) na estratosfera. A NH 3 pode levar a acidificação de ambientes terrestres e aquáticos, a eutrofização de sistemas aquáticos e produção de N 2 O. O SLMG vem sofrendo degradação da qualidade de suas á guas devido à urbanização e às atividades agropecuárias na região. Este sistema la gunar é composto por quatro lagoas interligadas entre si através de canais: Maricá, Ba rra, Padre e Guarapina. Para a análise de N 2 O foi utilizada a técnica da câmara estática flutua nte e 4 modelos de predição de fluxos (MPF). No caso da NH 3 foram feitas estimativas de fluxos também através de MPF. Os resultados deste estudo mostram que as quatro lagoa s do SLMG apresentam comportamentos distintos com relação aos fluxos dos dois gases ana lisados. As estimativas de taxas de emissão do sistema lagunar mostram que, apesar do sistema a presentar lagoas que parecem atuar como sorvedouro de N 2 O ou de NH 3 , num balanço geral, ele emite N para a atmosfera s ob uma ou outra forma. A taxa de emissão estimada variou entr e 92,15 g N dia -1 e 104,77 g N dia -1 . Outra informação que esta estimativa trouxe foi a d e que a maior parte das emissões ocorre sob a forma de NH 3 com emissão estimada de 84,79 g N dia -1 a 97,41 g N dia -1 . / This study examines the nitrous oxide (N 2 O) and ammonia (NH 3 ) fluxes in Maricá- Guarapina’s system. The N 2 O is a greenhouse gas and is involved in the consum ption of the ozone (O 3 ) in the stratosphere. The NH 3 can lead to acidification of terrestrial and aquat ic environments, eutrophication of aquatic systems and production of N 2 O. The SLMG is suffering degradation in the water’s quality due to urbanization and agricultural activities in the region. This system is composed for four lagoon interconnected between themselves through channels: Maricá, Barra, Father and Guarapi na. For the analysis of N 2 O was used the technique of the static chamber and 4 models predic tion fluxes (MPF). In the case of NH 3 were made estimates of fluxes through MPF too. The results of this study show that the four lagoons in the SLMG have different behaviors with r espect to the fluxes of the two gases analyzed. Estimates of the rates of emission in th e system lagoon show that despite the present system lagoons that seem act as sink of N 2 O and NH 3 , in a general balance, it gives N to the atmosphere in one form or another. The estim ated emission rate ranged between 92,15 g N -1 day -1 and 104,77 g N -1 day -1 . Other information that brought this estimate was that the majority of emissions occur in the form of NH 3 with estimated emission of 84,79 g N -1 day -1 to 97,41 g N -1 day -1 .
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Impact des éléments trace métalliques sur le milieu et apport de la cytométrie en flux dans l'étude du fonctionnement des lagunes de la décharge d'Etueffont (Territoire de Belfort, France) / Impact of the trace metal element on the environnment and the contribution of flow cytometry to the study of functioning of the lagoons discharge of Etuffont (Territory of Belfort, France

Al Ashoor, Ahmed Shaker 14 December 2016 (has links)
L’objectif de ce travail de thèse est d’évaluer le degré de contamination des différents compartiments du site de la décharge d’Étueffont à savoir : les lixiviats, les sédiments, l’eau souterraine, les poissons, les insectes et les microorganismes de la décharge d’Étueffont. Ce travail de recherche est structuré en neuf chapitres.Après une première partie (Part I) consacrée à une étude bibliographique, le deuxième chapitre (Part II) présente le site d’étude, c’est-à-dire l’installation de stockage de déchets non dangereux(ISDND) d’Étueffont. La troisième partie (Part III) est consacrée à l’analyse de la qualité des lixiviats dans les lagunes, les unités de stockage des déchets « Nouveau casier », « Sous casier », « Ancienne décharge », les ruisseaux du gros Pré et Mont Bonnet. La quatrième partie (Part IV) intitulée « Contamination métallique des sédiments du site de la décharge d’Étueffont », aborde l’étude de la variation spatiotemporelle des éléments traces métalliques au niveau des lixiviats et des sédiments dans les quatre lagunes du site de la décharge d’Étueffont. Afin de déterminer le degré de contamination métallique des lixiviats et des sédiments, nous avons procédé à un suivi de certains éléments localisés en amont, au milieu et en aval de chaque lagune avec un pas d’échantillonnage trimestriel entre octobre 2013 et avril 2016. La cinquième partie (Part V), complémentaire du chapitre précédent, définit plus précisément la distribution spatiale du panache à travers l’analyse de la qualité de l’eau souterraine au moyen de piézomètres. La sixième partie (Part VI) concerne les effets des métaux lourds sur les échanges gazeux et la fluorescence des chlorophylles chez (Typha latifolia). Le septième chapitre (Part VII) est consacré à l’étude des microorganismes de la décharge d’Etueffont : apport de la cytométrie en flux. Dans le huitième chapitre (Part VIII), nous aborderons l’étude de la bioaccumulation des éléments traces métalliques dans le Chironome Chironomus riparius. La dernière partie (Part IX) intitulée « Étude de la bioaccumulation des éléments traces métalliques au niveau des différents organes du gardon Rutilus rutilus», aborde l’étude de la bioaccumulation des éléments traces métalliques au niveau de différents organes (muscle, foie, arêtes et branchies). / The objective of this thesis work is to estimate the contamination level in the various compartments of the Étueffont discharge site namely: leachates, sediments, groundwater, fishes and insects. The microorganisms (< 10 µm) of the Étueffont discharge of were investigated at the single cell level by flow cytometry. This research work is structured in nine chapters.The first part (Part I), is dedicated to a literature review. Part II presents the study site, the storage of non-hazardous waste (ISDND) at Étueffont. Part III is dedicated to the analysis of leachate quality in lagoons, NC, SC, AD, MB and GP. Part IV addresses "Metal Sediment Contamination of Étueffont discharge site" It concerns the study of spatial and temporal variation of trace metals in leachate and sediment in the four lagoons landfill site of Étueffont. To determine the metal contamination level in leachate and sediment, we conducted follow-elements located upstream, middle and downstream in each lagoon with quarterly sampling between October 2013 and April 2016. Part V complements the previous chapter, by specifically defining the spatial distribution of the plume through the quality analysis of the piezometer groundwater. Part VI addresses the heavy metals impacts on gas exchange and chlorophyll fluorescence in (Typha latifolia). Part VII is dedicated to the microorganisms (<10 µm) investigation in the Étueffont discharge: by using flow cytometry. In the (Part VIII), we addressed the study of bioaccumulation of trace metallic elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd and Pb) in insect Chironomus riparius. Part IX entitled "Study bioaccumulation of trace metals in the various organs of roach Rutilus rutilus" concerns bioaccumulation of trace metals in different organs (muscle, liver, bones and gills) of this fish.
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Algal Bioprocess Development for Sustainable Wastewater Treatment and Biofuel Production

Mahapatra, Durga Madhab January 2014 (has links) (PDF)
Rapid urbanization has led to the generation of enormous wastewater after independence. The domestic wastewater generated in municipalities is rich in nutrients such as carbon, nitrogen and phosphorus along with other ions. The generated wastewater due to lack of adequate appropriate infrastructure including low treatment efficiencies are either untreated or partially treated and are let into water bodies. Present sewage treatment plants (STP’s) in the city are either under capacity or malfunctioning and hence are unable to meet the growing demand of burgeoning urban population. Water bodies have the ability to uptake nutrients (remediation by algae, bacteria, macrophytes) provided the wastewater inflow does not exceed the threshold. However, the sustained flow of wastewater beyond the water body’s treatment ability has led to the serious problem of nutrient enrichment in surface water bodies which is evident from algal bloom and profuse growth of invasive exotic macrophytes. This necessitates cost effective environmentally sound treatment options. The current research focuses on the characterisation of domestic wastewater fed ponds/lakes, understanding of nutrient regimes in wastewaters, pond dynamics, nutrient transformation and resource recovery. This has aided in devising an algae based treatment system for Bangalore city. The interplay between various biotic and abiotic factors governs water quality in a water body. Regular monitoring helps in characterisation of the water body and also helps in identifying the sources of external input (if any) to the system. Wastewater generated in urban localities in India, due to lack of adequate appropriate infrastructure including low treatment efficiencies are untreated or partially treated and are let into water bodies. Understanding the nature of the wastewater flow regimes and the turnover of biota with prevalent nutrient conditions is required to design treatment systems. Treatment involves breakdown of complex organism forms into simpler forms and transformations of organic nutrients into inorganic forms that are finally absorbed and assimilated by microbes as algae and bacteria. In wastewater fed urban pond systems, an array of microphytes as well as macrophytes grow and help in nutrient cycling in the system and still manage to remove nutrients to satisfactory levels. However, sustained inflow of wastewater with high nutrients results in the deterioration of the system as nutrient input exceed the supportive and assimilative capability resulting in proliferation of macrophytes, algal blooms, froth formations rendering the system anoxic that results in the loss of functional abilities of the urban pond systems. This biota in the system plays a major role in nutrient removal and recycles. Understanding the nutrient cycling aspects of urban wastewater fed systems is essential to find out the key players in treatment and for devising a sustainable treatment option with resource recovery. The review of wastewater generation, treatment systems highlight shortfall of the treatment systems and need for sustainable treatment for removal and recovery of nutrients such as C, N and P. Characterisation of Varthur water body (spatial extent 220 ha) located in the south of Bangalore city has been done through monthly monitoring for 18 months with the analyses of physico-chemical and biological. The analysis showed BOD removal of 70% (filterable) when the lake functioned as an anaerobic–aerobic lagoon for 6 months at an estimated residence time of 5 days. During this period, the biota of the lake, especially primary producers such as algae, treat the water through remediation of nutrients to nearly standard water quality levels. However, the growth and spread of invasive exotic macrophytes such as water hyacinth rendered the lake anaerobic which reduces its ability (due to absence of low algae) to treat the water. This highlights the role of algae especially Chlorophycean members as Chlorococcum sp., Chlorella sp. and Monoraphidium sp. in treating urban domestic wastewater and the scope for introducing algal ponds/lagoons to treat wastewater treatment and it may be used in a larger number of small towns to enable local reuse of water. The entire pond systems comprises of various components that are deeply affected by the biotic and abiotic factors in the system. Hence, studies on major biotic components were conducted especially on algae and macrophytes and the impact of abiotic factors as wind, light, and precipitation with seasonality’s. The diurnal and spatio-temporal variations in the dissolved oxygen as well other treatment parameters were used for zonation through multivariate analysis. Physico-chemical parameters confirm the nutrient enrichment (high Amm.-N) in the water body due to the sustained inflow of wastewater. High levels of nutrients together with BOD have resulted in the lower DO levels affecting the biological life. Study on biota revealed macrophytes altering the photosynthetic regime in the algae in water bodies thus, creating anoxia and nutrient re-suspension. The multivariate analysis showed three distinct zones (clusters) on the basis of physico-chemical variables and nutrient concentrations in the lake. The sedimentary C and N analysis showed a steady increase in the C: N ratio as a function of residence time. Importance of the various sub-systems in the water body in terms of nutrient uptake and accumulation showed algal systems to be efficient. C budgeting accounted to ~ 7 t/d i.e. ~2574 t/y, indicated that the lake is an accumulator of C. An estimated relatively high gas emission across the water/air interface (17 t/d) to carbon burial into sediments (2.3 t/d) further indicates very high emissions compared to sedimentation showing the dominance of internal C cycles. The overall mass balance, gas exchange and carbon burial balance showed Varthur water body as a major emitter of C due to high primary production, substantive allochthonous carbon inputs and intensive anthropogenic activities in the water body. Gaseous carbon emission accounted for 28 % of the total Influx C. The spatial profile of N in sediment ranged from 2280-3539 mg/kg of sediment dry mass. Very low value of N:P ratio in sediments suggested possible N limitation. The determination of ammonification and nitrification showed lower nitrification rates than the ammonification rates. The potentially mineralisable nitrogen content in Varthur pond sediments varied greatly from 21.65% to 75.54% and was strongly correlated (r2=0.85) to sedimentary TN. N budgeting showed NH4-N as the predominant Nr form for microbial uptake and is the major mechanism for nitrogen removal, followed by the sedimentation process. Bacterial biomass, algal biomass and macrophyte biomass accounted for 14, 4 and 1% N removal, respectively. Ammonium concentration and nitrification accounted for 27% and 2%, respectively. While bacterial uptake remained fairly constant throughout the year, micro-algae was the major player during monsoon and winter and macrophytes dominated Nr capture during summer among autotrophs. From the estimates, it has been observed that nearly 55% Nr was recovered, recycled as cell mass and transferred to a crop system when such N-captured water is used for irrigating fodder crops. About 45% of N input into the system was lost and methods to reduce this loss need to be evolved in the future. The spatial profile of P in sediment ranged from 2111.35-3982.03 mg/kg of sediment dry mass. Inorganic-P (IP) ranging from 1270.27-3505.73 mg/kg was found to be the major fraction (61.16-91.56%) of sedimentary P. High p values in both water columns and sediments showed potential P excess conditions. P concentrations in micro and macro-algae collected during the due course of the study (on dry biomass basis) were 0.347% and 0.939% P respectively. The P fractionation revealed metal oxide bound P (NaOH-P) and constituted major fraction of IP indicating, high concentrations of Fe and Al in sediments. High concentrations of sedimentary N and P indicated possible higher trophic status (bio-productivity/unit volume) signifying its towering nutrient status evidenced from the rank order of P fractions: NaOH-P > HCl-P > NH4Cl-P, which is specific for highly enriched water bodies. P budgeting showed that bulk of the P is trapped in sediment layer with a potential of ~50 % recovery from the sediments indicating, ~70% P retention within the system. The biotic components such as bacteria, algae and macrophytes accumulates a substantial amount of P, immobilising ~139, ~482 and ~131 tonness/yr of P. The sequential P extraction shows that ~70 % of sediment bound P is readily reducible during anoxic conditions which can potentially become bio-available to trigger algal growth. Assessment of treatment efficiency of facultative algal ponds, showed moderate treatment levels with 60 % total COD removal, 50% of filterable COD removal; 82% of total BOD removal and 70% of filterable BOD removal. The N removal efficiency was lower. However, a rapid decrease in the suspended solids after a faster euglenoids growth indicated particulate C removal by algal ingestion. Euglenoides dominated the facultative pond and Chlorophycean members were more abundant in the maturation ponds owing to variable surface BOD loadings. Significant correlations between algal biomass and nutrients indicate the importance of the type and nature of algal communities that can be used as an efficient tool for predicting the dynamics of various phases in wastewater treatment systems. Detailed morphological analysis of dominant algal species i.e. euglenoides was also performed. Euglenophycean members (>14 species) sampled from various locations in the facultative pond based system showed various striae patterns and distinct nano channels on the cell surface that might have possible role in cell secretions. Comparative assessment of treatment systems reveal that algal pond systems performed well under higher organic load with a COD removal efficiency of 70%, TN removal efficiency of 73% and TP removal efficiency of 22%. However, the facultative pond based systems were effective in suspended solid (SS) removal up to 93% and BOD removal up to 82%. The conventional wastewater treatment systems were efficient in terms of SS removal up to 88%, COD removal up to 74% and BOD removal up to 63%, but were highly ineffective in nutrient removal. The evaluation of treatment processes in mechanically aerated systems, facultative ponds and large shallow lake based systems in terms of capital and annual O&M costs, COD removal cost and land requirements reveals that the mechanical systems require 5 times more capital and O&M costs than ponds. The treatment systems were also ranked in terms of the total annual cost (e.g., capital, manpower, chemical, repair, electricity, land). It showed that algal pond systems followed by facultative pond based system are economically better choice than mechanical technologies. Finally, it was found that the large pond based systems could be economically the best option for the developing countries considering all factors, including economic viability and treatment efficiency. The treatment efficiency analysis showed that algal pond systems were the most effective options for treating urban wastewater. Culturing native wastewater species in growth media and wastewaters, assessment of efficient cell disruption and solvent systems, lipid profiles of wastewater algal species were studied. Wastewater grown algal species as Euglena sp., Spirogyra sp., Phormidium sp., Lepocinclis ovum, and Chlorococcum sp. are comparatively rich in lipids. These algae grow mixotrophically and can store substantial amount of wastewater carbon as TAG’s in varied environments. Among the different cell disruption methods used for the study, sonication was the most effective. The combination of maceration and methanol: chloroform: water (2:1:0.8, v/v) (Bligh and Dyer’s, solvent) gave highest lipid extraction yield among other combinations. Further more these wastewater algae as Lepocinclis ovum and Chlorococcum sp. were found to grow better in wastewaters. Increased lipid content was recorded during the cell cultures with accumulation of quality FAME with high saturates predominated by C16-C18 fatty acids. These wastewater algal lipids are suitable for bio-energy generation with potential biomass productivity (6.52 t/ha/yr) of wastewater-grown species as Euglena. The studies on Euglena sp. showed mixotrophic mode that offers an efficient removal of TOC, N and P from domestic wastewater without any pre-treatment. Lipid profiles of the extracted algal oil were similar to the vegetative feedstock oils, indicating a good quality fuel for energy generation. Mixed algal consortia’s bioremediation potential (removal of nutrients) with the scope for biofuel production highlights self flocculating abilities of algal consortia aided in the effective treatment of wastewater with substantial algal harvest. Studies on cultivating wastewater algal consortia in novel cascading algal parcel flow reactor (CAPFR) operating in continuous mode showed 70-80 % nutrient and ~90 % C removal with in a residence time of ~4 days with highest cell densities (0.91 g/l) and productivities (0.26 g/l/d) in the last stages. The lipid contents varied from 26-28 % with highest lipid productivities ~58 mg/l/d in the 2nd phase of the bioreactor. Most of the lipids were associated with the pigments as chlorophyll and carotenoids. Furthermore, the algal rector removed bacteria up to 4 log orders. Essential cations and phosphates were responsible for self clumping of algal biomass in the final stages with a high internal P content within the cell. The algal biomass also showed substantial exothermic peaks and high heat values (~18 MJ/kg). Studies on continuous cultivation of Dictyosphaerium sp. showed that this species could adapt to wastewater conditions and also showed good nutrient removal at lower HRT (2.5 days). The high biomass productivities with high lipid content (~36%) at low HRT in the continuous mode offer potential options for economic and feasible nutrient removal with biofuel production. Investigations on city wastewaters showed low nutrient ratio indicating C limitations and possible scope for algal wastewater treatment. Integration of algal ponds in the present treatment network requires an additional land ranging from ~0.37 to 2.75 ha to treat an MLD of wastewater depending on the nutrient content and influent waters fed to algal systems. The treatment plants require an additional ~1.6 ha of land to treat 1 MLD of wastewater considering an average N and P values of 18 and 5 mg/l. The continuous algal bio-processes implemented at decentralised levels would help in the economical ways for nutrient removal and recycling of the nutrient free waters after treatment. This meets multiple objectives of low cost treatment of wastewater, nutrient recovery and fuel production. Algal nutrient capture and consequent biofuel production would ensure sustainability through i) water purification ii) nutrients capture and iii) biofuel to meet the growing energy demand, and would be an optimal treatment option for urban wastewater. The thesis consists of 10 chapters and basically deals with the development of a sustainable and economically viable bioprocess for wastewater treatment and biomass production. Chapter 1 provides a brief introduction to wastewater; domestic wastewater composition, generation and treatment in developing nations and in the country and review of the various techniques for treatment of domestic wastewaters, advantages of algal processes in nutrient removal (C, N and P) and production of valued by-product such as lipid generation, for its use as biofuel. Chapter 2 is based on primary field investigations in a wastewater fed urban water body/pond systems involving monthly sampling and analysis of various physico-chemical and biological parameters. Assessment of treatment capabilities of the continuous systems through detailed characterisation of treatment parameters is explained in the second chapter. Chapter 3 discusses the role of the major biotic (algae and macrophytes) and abiotic factors in nutrient transformations, the diurnal variations in parameters especially dissolved oxygen, multivariate spatio-temporal analysis of functional abilities for zoning, the activities in the sludge/sediment and transitions in the CN ratio as a function of residence time. Chapter 4 involves studies in C, N and P quantification and budgeting in such pond systems and partitioning of the nutrients and their distribution in various biotic and abiotic subsystems. This chapter also highlights the major nutrient losses from the system and un-utilised nutrient stocks, paving way for beneficial use of nutrients from such man made lagoon wastewater systems. Chapter 5 discusses the mechanisms and efficacies of algal pond based treatment systems through a detailed study and highlight its advantages over the mechanical ASP based systems. This has been done through a comparative assessment of treatment efficiency, economics and environmental externalities. This study also provides necessary insights and potential of wastewater algal species such as Euglena for its abilities in nutrient removal and biomass generation. This provides insights to algal treatment options for optimal resource recovery and utilisation from wastewaters. Chapter 6 focuses on testing the growth, biomass and lipid production of various wastewater algae isolated from treatment ponds. The chapter identifies suitable cell disruption and extraction routes for efficient lipid extraction and assesses the potential of these wastewater grown algae for regional and national biofuel production. Chapter 7 discusses the effectiveness of wastewater grown Euglena sp. and algal consortia in nutrient removal and as a source of lipids for biofuel generation. Chapter 8 involves the design and operation of a continuous algal (uni-algal/algal consortia) bioreactor devised taking insights from earlier field based studies and their potential as efficient urban wastewater treatment systems. Chapter 9 discusses the present nutrient levels in the city wastewaters and also an analysis of the temporal and spatial variation of nutrients in city sewers and elaborates the scope for integration of the algal modules i.e. continuous algal bioreactors (designed in the previous chapter) into existing STP’s. Chapter 10 elaborates significant contributions and outcome of the research.
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[pt] DEGRADAÇÃO AMBIENTAL NO COMPLEXO LAGUNAR DE JACAREPAGUÁ NA CIDADE DO RIO DE JANEIRO: O PAPEL DA GOVERNANÇA / [en] ENVIRONMENTAL DEGRADATION OF THE JACAREPAGUÁ LAGOON SYSTEM IN THE CITY OF RIO DE JANEIRO: THE ROLE OF THE GOVERNANCE

SILVANA DI IULIO MOREIRA 26 September 2022 (has links)
[pt] A qualidade das águas dos corpos hídricos nas áreas urbanas é normalmente comprometida em função da grande quantidade de lançamento de esgotos com ou sem tratamento inadequado, trazendo impactos ambientais, econômicos e sociais. Esta pesquisa tem o objetivo de analisar a capacidade de gestão e os arranjos de governança de instituições e agentes públicos responsáveis pelo saneamento do complexo lagunar de Jacarepaguá e a existência de um arcabouço de leis ambientais. A partir da revisão bibliográfica pesquisou-se o histórico da ocupação e do desenvolvimento da infraestrutura urbana da região onde está situado o complexo lagunar. Os boletins da qualidade das águas das lagoas e rios foram levantados do período de 2013 a 2019. Os resultados obtidos são comparados com os resultados de estudos científicos realizados com dados que retroagem ao início dos anos 80. A legislação das matérias de recursos hídricos e saneamento foram pesquisadas com objetivo de identificar as atribuições dos atores envolvidos. Constatou-se que as águas do complexo lagunar apresentam um alto grau de poluição com enorme aporte de esgoto in natura e que as causas são as consequências de irresponsabilidade e omissão dos diversos atores que atuam no planejamento, na fiscalização, na regulação, no controle e na prestação dos serviços de esgotamento sanitário. Somam-se a isso um conflito de competência entre o Estado e o Município, ocupações irregulares e o mau funcionamento de instalações privadas. / [en] The major economy of the city of Rio de Janeiro is tied into its tourism and leisure industry, due to its unique natural beauty of its landscape. The unique combination of mountains meeting the sea has earned it the title given by UNESCO of the First Urban and Cultural Landscape declared World Heritage. This takes into consideration the area s natural and urban monuments of the South zone, in particular, but recognizes the unique relationship between man and nature, and the balance between natural and man-made elements. It considers the environmental and social interaction, which enables its citizens to enjoy various forms of leisure activities associated with the area s unique natural beauty. However, despite this designation, on the west side of the city, there are found other natural beauties, including the coastal lagoons of the Jacarepaguá lagoon system. But here, the environment has been completely neglected by the government. In these lagoons, people cannot fish, sail, or swim. The use of these ecological sites is prohibited due to the contamination of the waters. A natural heritage for all, the waters have become degraded with the presence of raw sewage, which causes the foul smell, disease, and the reduced presence of fauna and flora. Unregulated construction on its banks and on the edges of its tributaries has caused these bodies of water to become filled with garbage, sand, and all sorts of debris, besides the sewage. From its primitive origin until the implementation of the Urbanist Lúcio Costa s plan, the region remained preserved. Corrêa (1933), testified crystal clear water lagoons and flooded green fields where fishing, hunting, and natural resources were abundant. However, even at this early date, he observed the degradation of forests and the hunting of animals out of control, and recorded a lack of regulation by the governing body, the Water and Sewage Inspectorate. He therefore suggested, inspired by the laws of the Office International pour la Protection de la Nature, the creation of a biological reserve for Marapendi lagoon, realized in 1965.

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